3 * Copyright (c) 2005 Konstantin Shishkov
5 * This file is part of FFmpeg.
7 * FFmpeg is free software; you can redistribute it and/or
8 * modify it under the terms of the GNU Lesser General Public
9 * License as published by the Free Software Foundation; either
10 * version 2.1 of the License, or (at your option) any later version.
12 * FFmpeg is distributed in the hope that it will be useful,
13 * but WITHOUT ANY WARRANTY; without even the implied warranty of
14 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
15 * Lesser General Public License for more details.
17 * You should have received a copy of the GNU Lesser General Public
18 * License along with FFmpeg; if not, write to the Free Software
19 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
46 typedef struct LOCOContext {
47 AVCodecContext *avctx;
52 typedef struct RICEContext {
54 int save, run, run2; /* internal rice decoder state */
55 int sum, count; /* sum and count for getting rice parameter */
59 static int loco_get_rice_param(RICEContext *r)
64 while (r->sum > val && cnt < 9) {
72 static inline void loco_update_rice_param(RICEContext *r, int val)
83 static inline int loco_get_rice(RICEContext *r)
86 if (r->run > 0) { /* we have zero run */
88 loco_update_rice_param(r, 0);
91 v = get_ur_golomb_jpegls(&r->gb, loco_get_rice_param(r), INT_MAX, 0);
92 loco_update_rice_param(r, (v + 1) >> 1);
95 r->run = get_ur_golomb_jpegls(&r->gb, 2, INT_MAX, 0);
97 r->save += r->run + 1;
103 v = ((v >> 1) + r->lossy) ^ -(v & 1);
116 /* LOCO main predictor - LOCO-I/JPEG-LS predictor */
117 static inline int loco_predict(uint8_t* data, int stride, int step)
123 c = data[-stride - step];
125 return mid_pred(a, a + b - c, b);
128 static int loco_decode_plane(LOCOContext *l, uint8_t *data, int width, int height,
129 int stride, const uint8_t *buf, int buf_size, int step)
138 init_get_bits8(&rc.gb, buf, buf_size);
147 /* restore top left pixel */
148 val = loco_get_rice(&rc);
150 /* restore top line */
151 for (i = 1; i < width; i++) {
152 val = loco_get_rice(&rc);
153 data[i * step] = data[i * step - step] + val;
156 for (j = 1; j < height; j++) {
157 /* restore left column */
158 val = loco_get_rice(&rc);
159 data[0] = data[-stride] + val;
160 /* restore all other pixels */
161 for (i = 1; i < width; i++) {
162 val = loco_get_rice(&rc);
163 data[i * step] = loco_predict(&data[i * step], stride, step) + val;
168 return (get_bits_count(&rc.gb) + 7) >> 3;
171 static int decode_frame(AVCodecContext *avctx,
172 void *data, int *got_frame,
175 LOCOContext * const l = avctx->priv_data;
176 const uint8_t *buf = avpkt->data;
177 int buf_size = avpkt->size;
178 AVFrame * const p = data;
181 if ((ret = ff_get_buffer(avctx, p, 0)) < 0)
185 #define ADVANCE_BY_DECODED do { \
186 if (decoded < 0 || decoded >= buf_size) goto buf_too_small; \
187 buf += decoded; buf_size -= decoded; \
190 case LOCO_CYUY2: case LOCO_YUY2: case LOCO_UYVY:
191 decoded = loco_decode_plane(l, p->data[0], avctx->width, avctx->height,
192 p->linesize[0], buf, buf_size, 1);
194 decoded = loco_decode_plane(l, p->data[1], avctx->width / 2, avctx->height,
195 p->linesize[1], buf, buf_size, 1);
197 decoded = loco_decode_plane(l, p->data[2], avctx->width / 2, avctx->height,
198 p->linesize[2], buf, buf_size, 1);
200 case LOCO_CYV12: case LOCO_YV12:
201 decoded = loco_decode_plane(l, p->data[0], avctx->width, avctx->height,
202 p->linesize[0], buf, buf_size, 1);
204 decoded = loco_decode_plane(l, p->data[2], avctx->width / 2, avctx->height / 2,
205 p->linesize[2], buf, buf_size, 1);
207 decoded = loco_decode_plane(l, p->data[1], avctx->width / 2, avctx->height / 2,
208 p->linesize[1], buf, buf_size, 1);
210 case LOCO_CRGB: case LOCO_RGB:
211 decoded = loco_decode_plane(l, p->data[0] + p->linesize[0]*(avctx->height-1), avctx->width, avctx->height,
212 -p->linesize[0], buf, buf_size, 3);
214 decoded = loco_decode_plane(l, p->data[0] + p->linesize[0]*(avctx->height-1) + 1, avctx->width, avctx->height,
215 -p->linesize[0], buf, buf_size, 3);
217 decoded = loco_decode_plane(l, p->data[0] + p->linesize[0]*(avctx->height-1) + 2, avctx->width, avctx->height,
218 -p->linesize[0], buf, buf_size, 3);
222 decoded = loco_decode_plane(l, p->data[0] + p->linesize[0]*(avctx->height-1), avctx->width, avctx->height,
223 -p->linesize[0], buf, buf_size, 4);
225 decoded = loco_decode_plane(l, p->data[0] + p->linesize[0]*(avctx->height-1) + 1, avctx->width, avctx->height,
226 -p->linesize[0], buf, buf_size, 4);
228 decoded = loco_decode_plane(l, p->data[0] + p->linesize[0]*(avctx->height-1) + 2, avctx->width, avctx->height,
229 -p->linesize[0], buf, buf_size, 4);
231 decoded = loco_decode_plane(l, p->data[0] + p->linesize[0]*(avctx->height-1) + 3, avctx->width, avctx->height,
232 -p->linesize[0], buf, buf_size, 4);
238 if (decoded < 0 || decoded > buf_size)
244 return avpkt->size - buf_size;
246 av_log(avctx, AV_LOG_ERROR, "Input data too small.\n");
247 return AVERROR(EINVAL);
250 static av_cold int decode_init(AVCodecContext *avctx)
252 LOCOContext * const l = avctx->priv_data;
256 if (avctx->extradata_size < 12) {
257 av_log(avctx, AV_LOG_ERROR, "Extradata size must be >= 12 instead of %i\n",
258 avctx->extradata_size);
259 return AVERROR_INVALIDDATA;
261 version = AV_RL32(avctx->extradata);
267 l->lossy = AV_RL32(avctx->extradata + 8);
270 l->lossy = AV_RL32(avctx->extradata + 8);
271 avpriv_request_sample(avctx, "LOCO codec version %i", version);
274 l->mode = AV_RL32(avctx->extradata + 4);
279 avctx->pix_fmt = AV_PIX_FMT_YUV422P;
283 avctx->pix_fmt = AV_PIX_FMT_BGR24;
287 avctx->pix_fmt = AV_PIX_FMT_YUV420P;
291 avctx->pix_fmt = AV_PIX_FMT_BGRA;
294 av_log(avctx, AV_LOG_INFO, "Unknown colorspace, index = %i\n", l->mode);
295 return AVERROR_INVALIDDATA;
297 if (avctx->debug & FF_DEBUG_PICT_INFO)
298 av_log(avctx, AV_LOG_INFO, "lossy:%i, version:%i, mode: %i\n", l->lossy, version, l->mode);
303 AVCodec ff_loco_decoder = {
305 .long_name = NULL_IF_CONFIG_SMALL("LOCO"),
306 .type = AVMEDIA_TYPE_VIDEO,
307 .id = AV_CODEC_ID_LOCO,
308 .priv_data_size = sizeof(LOCOContext),
310 .decode = decode_frame,
311 .capabilities = CODEC_CAP_DR1,